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How to challenge blood and breath tests in Texas

On Behalf of | Mar 19, 2024 | Firm News |

If you’re facing DWI charges in Texas, it’s crucial to understand that a blood or breath test result indicating intoxication isn’t the final word on your case. Both tests are subject to a variety of errors and defenses that may be available to you.

Blood and breath tests are designed to measure blood alcohol concentration (BAC). In Texas, a BAC of 0.08% or higher is considered legally intoxicated. However, the reliability of these tests can be compromised by several factors, ranging from improper administration to machine malfunctions.

Breath and blood test defenses

Blood tests are often thought to be the most accurate measure of BAC, but they are not infallible. The following issues can affect the accuracy of blood test results:

  • Improper storage and handling: blood samples must be stored and handled according to strict protocols. Mishandling or contamination can lead to fermentation or other chemical changes, skewing results.
  • Chain of custody issues: any break in the chain of custody may cast doubt on the integrity of the sample and, consequently, the test results.
  • Testing method flaws: the type of test used to analyze the blood sample can affect accuracy. Gas chromatography, the standard testing method, requires precise calibration and maintenance.

Breath tests are more common but also more prone to error. Some defenses include:

  • Machine calibration and maintenance: breath testing devices must be regularly calibrated and maintained. Failure to do so can result in inaccurate readings.
  • Operator error: the officer administering the test must be properly trained and follow exact procedures. Deviations can lead to challenges in the results.
  • Physiological factors: a person’s medical conditions, diet, and even temperature can affect breath test results.

Challenging blood and breath test results requires a deep understanding of the science and legal procedures involved.

You deserve a fair trial.

The evidence against you in trial carries a lot of weight, but it also demands close scrutiny. Carelessness and errors in the collection and interpretation of physical evidence are a severe problem and more than that, a violation of your rights.

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